This invention relates to a radio communication apparatus or device for use in carrying out an operation in response to a call signal. The radio communication apparatus may be a radio paging receiver, a transceiver, or the like, although description will be mainly directed to the radio paging receiver.
A radio paging receiver of the type described includes a receiving circuit for carrying out a receiving operation of selectively receiving a call signal specific to the apparatus. The receiving circuit produces a received signal whenever the receiving circuit receives the call signal. On production of the received signal, the radio paging receiver perceptually or sensorily gives notice of receiving the call signal too a possessor or user. Such a perceptual or sensory notice may be given in an audible manner and/or in a visible manner.
A wide variety of radio paging receivers are already known which audibly notify the reception of the call signal. By way of example, such a radio paging receiver is disclosed in Japanese Unexamined Utility Model Registration Publication No. Syo 55-61,315, namely, 61,315/1980. The radio paging receiver disclosed in the above-mentioned publication comprises a volume mode switch for producing a volume mode signal indicative of one of some kinds of volume and a control circuit for making the tone generator generate the audible tone in the volume indicated by the volume mode signal, each time on reception of a call signal. Thus, the audible tone is generated regardless of reception times of the call signals.
Other similar radio paging receivers are also disclosed in U.S. Pat. No. 4,237,448 and in Japanese Utility Model Registration Publication No. Syo 58-43,302 (43,302/1983). In each of the receivers, an audible tone is generated in a volume which is gradually grown, each time when a call signal is received. Such a growing audible tone itself is invariable even when the call signal is repeatedly received many times.
Still another radio paging receiver is revealed in Japanese Unexamined Patent Publication No. Syo 61-177,035 (177,035/1986). The radio paging receiver comprises a light emitting diode (LED) for emitting visible light and a control circuit responsive to the call signal for making the light emitting diode intermittently emit the visible light without generation of the audible tone when the receiver is put into a silent mode. Thus, the radio paging receiver visually notifies reception of the call signal each time when the call signal is received. In other words, visual displays are provided so as to visually notify the reception of the call signal.
At any rate, each of such conventional radio paging receivers audibly or visually notifies reception of the call signal in the manner determined for each radio paging receiver. However, such audible or visual notification in each radio paging receiver never depends on reception times of the call signal. In other words, even when the call is repeatedly received many times and is very urgent and important, the possessor can not recognize such urgency or importance of the call signal.